RT Journal Article SR Electronic T1 LENS EFFICIENCY—A CLINICAL CONCEPT JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 291 OP 298 DO 10.1136/bjo.30.5.291 VO 30 IS 5 A1 Pascal, Joseph I. YR 1946 UL http://bjo.bmj.com/content/30/5/291.abstract AB